Fabric conditioning compositions containing 2-20% active ingredients are widely used during laundering. They make the laundered fabrics softer to touch, fluffier and reduce static. The two main classes of product used individually for the above purposes are quaternary ammonium compounds (QAC) or Imidazoline salts. Sometimes even a combination of the two is used at this 2-20% active level ingredients to get optimum results vis-a-vis softening/antistatic cost and freeze/thaw. (The remaining portion being mainly solvents). In order to make such a product, the manufacturer has to prepare the mix from individual concentrates of 75% quaternary ammonium compounds (QAC) and imidazoline salts. This means that the compounder has to keep an inventory of the individual softeners. Also, QAC at conc of 74% or higher have been found so far to crystallize and become hard upon standing, and/or during shipping on long journeys. In other words, when shipped in drums they do become not pumpable.
To make a mixture of the 2 softeners to the usual marketable concentration of 2.5 to 6, it is necessary to make the compound pumpable at the concentration of 75% which sometimes involves heating which can be dangerous and expensive. For both economic reasons (heating involving additional cost), and the reason for safety, heating is a problem.
On the other hand, concentrates, and if feasible, super concentrates, are highly desirable since diluents add to shipping and thereby to the cost of the final product.